Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a548e9b4aa4b924…

MALICIOUS

PDF

101.0 KB Created: 2021-07-02 17:41:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c6b8f4502961bee283c3bfe0a9803864 SHA-1: 0a3674729ba8fd951c5fc310c1be2b59f6433c57 SHA-256: 7a548e9b4aa4b924971eafb49c36871cfd27d13796755418cc401c6ed9d68c9a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF document was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, indicating an attempt to hide its true purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9803

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/lhrm9sgulge4va5lgfd3g0c5jb/vusag.pdf
    • http://associacaoguainumbi.org.br/wp/wp-content/plugins/formcraft/file-upload/server/content/files/16087c70e44e48---zurijapesisusejivoxikego.pdf
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/5fbd6a00d4d162a06dbea4328ffceee3/pigatogozejowu.pdf
    • https://shared401k.com/wp-content/plugins/super-forms/uploads/php/files/fa0ee8ae5428e62b8d899ac7b95f9fac/xiditopitawolabo.pdf
    • http://good163.cn/Uploadfiles/files/75969367874.pdf
    • https://www.vbclighting.com/wp-content/plugins/super-forms/uploads/php/files/db1d8395860f20c03d330d11b2bbfcfb/13885373394.pdf
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077898a654c8---37169141161.pdf
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1609770f49fc79---pidojesawe.pdf
    • http://stewartreunion2020.com/clients/2/2a/2a0d9dcdd57715375c9f4393c24df0f2/File/37836748305.pdf
    • http://cioccolatogallucci.it/userfiles/file/sedurajijepokidarot.pdf
    • http://gabortech.comadmin/file/mutudamarakisud.pdf
    • http://rzn-house.ru/upload/file/39603236123.pdf
    • http://planetamama.ru/files/file/kedukesizasenum.pdf
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9b74972ca9---kifagefefuzosimowuwu.pdf
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/5ab38644f70da185e9b669b7131709ce/filanudofatuleke.pdf
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ba3bdd7b5a6---81943812356.pdf
    • https://harom.ro/files/file/belumexizifu.pdf
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607181cebf1d3---58274164955.pdf
    • https://pasarantogel.com/contents//files/48052676383.pdf
    • http://arablift.net/userfiles/file/27484962426.pdf
    • http://sns.hu/_user/file/sukoruxewin.pdf
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/07d3ce2b055c34eece1a203b1b2aecbe/41971003100.pdf
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606cf8f63124a---vapomibadawinibelodowot.pdf
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/097cdce62586308abd05daca7465de12/84936574590.pdf
    • https://fceresources.com/ckfinder/userfiles/files/80605330717.pdf
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a745a244e7b---11034812195.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=path+of+exile+item+level
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000129e3.bin
13323ed1afce0ae6fedca66071d9efcffe295632521e324fe49f9975293a1fa2
pdf-font-stream PDF embedded font (sfnt) at offset 0x129E3 17340 bytes
font_01_sfnt_off00015747.bin
aa3ef720d304ab8bc2bc508f7f10aac07d8be2d7b187d950708af92b285dbd1c
pdf-font-stream PDF embedded font (sfnt) at offset 0x15747 10276 bytes
font_02_sfnt_off00016e74.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x16E74 16792 bytes